Li Pan-Pan, Huang Ye-Meng, Cai Qi, Huang Li-Li, Song Yu, Guan Huai-Jin
Department of Ophthalmology, Nantong City No.1 People's Hospital and Second Affiliated Hospital of Nantong University, Nantong 226000, Jiangsu Province, China.
Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong 226000, Jiangsu Province, China.
Int J Ophthalmol. 2019 Aug 18;12(8):1277-1282. doi: 10.18240/ijo.2019.08.07. eCollection 2019.
To examine the effects of one-handed phacoemulsification with steep-axis incision on corneal curvature and analyze surgically induced astigmatism (SIA) on the true net power, anterior and posterior corneal surfaces.
Patients with cataracts underwent one-handed phacoemulsification with a 2.4-mm steep-axis of clear corneal incision (CCI) based on true net power. CCI was created under the guidance of Verion. Central corneal thickness (CCT), keratometry readings of the true net power and anterior and posterior corneal surface were obtained using Pentacam. Biometry, such as axial length, anterior chamber depth (ACD) and white-to-white (WTW) were performed using Lenstar pre- and 3mo post-operatively.
The study evaluated 68 eyes of 65 patients. The mean age was 65.93±9.40y; CCT was 529.21±37.40 µm; WTW was 11.59±0.35 mm. Regarding true net power, keratometric value at the flattest corneal meridian for the 3-mm central zone (Ks) was significantly decreased postoperatively (=0.031). Keratometric value at the steepest corneal meridian for the 3-mm central zone (Kf) was increased postoperatively (>0.05). Astigmatism of true net power was 1.21±0.56 D preoperatively and significantly decreased to 1.02±0.58 D postoperatively (=0.021). On the anterior corneal surface, no significant difference in Ks and Kf was noted pre- versus postoperatively. Anterior corneal astigmatism was 1.08±0.51 D preoperatively and significantly decreased to 0.87±0.46 D postoperatively (=0.002). On the posterior corneal surface, Ks and Kf were significantly increased postoperatively (all <0.05), and posterior corneal astigmatism also increased (=0.008). The SIA values of true net power and the anterior and posterior corneal surfaces at 3mo postoperatively were 1.26±0.63 D (range: 0.11 to 2.80 D), 1.05±0.54 D (range: 0.23 to 2.40 D), and 0.21±0.17 D (range: 0.01 to 0.07 D), respectively.
One-handed phacoemulsification with steep-axis incision can effectively decrease astigmatism of true net power and anterior corneal astigmatism. In the same surgery, the difference in personal SIA potentially originated from a difference in personal corneal thickness and diameter, both CCT and WTW distance should always be measured preoperatively when planning steep-axis phacoemulsification.
探讨采用陡峭轴切口的单手白内障超声乳化术对角膜曲率的影响，并分析手术源性散光（SIA）在真实净度数、角膜前后表面上的情况。
白内障患者基于真实净度数接受采用2.4毫米陡峭轴透明角膜切口（CCI）的单手白内障超声乳化术。在Verion引导下制作CCI。使用Pentacam获取中央角膜厚度（CCT）、真实净度数以及角膜前后表面的角膜曲率读数。术前和术后3个月使用Lenstar进行生物测量，如眼轴长度、前房深度（ACD）和白对白（WTW）。
该研究评估了65例患者的68只眼。平均年龄为65.93±9.40岁；CCT为529.21±37.40微米；WTW为11.59±0.35毫米。关于真实净度数，术后3毫米中央区最平坦角膜子午线处的角膜曲率值（Ks）显著降低（P = 0.031）。术后3毫米中央区最陡峭角膜子午线处的角膜曲率值（Kf）升高（P>0.05）。真实净度数的散光术前为1.21±0.56 D，术后显著降至1.02±0.58 D（P = 0.021）。在角膜前表面，术前与术后Ks和Kf均无显著差异。角膜前散光术前为1.08±0.51 D，术后显著降至0.87±0.46 D（P = 0.002）。在角膜后表面，Ks和Kf术后均显著升高（均P<0.05），角膜后散光也升高（P = 0.008）。术后3个月真实净度数、角膜前后表面的SIA值分别为1.26±0.63 D（范围：0.11至2.80 D）、1.05±0.54 D（范围：0.23至2.40 D）和0.21±0.17 D（范围：0.01至0.07 D）。
采用陡峭轴切口的单手白内障超声乳化术可有效降低真实净度数的散光和角膜前散光。在同一手术中，个体SIA的差异可能源于个体角膜厚度和直径的差异，在计划进行陡峭轴白内障超声乳化术时，术前应始终测量CCT和WTW距离。
